document.write( "Question 1152966: you invested $5000 between two accounts paying 7% and 9% annual interest, respectively. If the total interest earned for the year was $390 how much was invest at each rate? \n" ); document.write( "

Algebra.Com's Answer #775106 by ikleyn(52858) $\"\"$ $\"About$

You can put this solution on YOUR website!
.
\n" ); document.write( "

\r\n" );
document.write( "\r\n" );
document.write( "Let x = amount invested at 9%.\r\n" );
document.write( "\r\n" );
document.write( "Then amount invested at 7% is (5000-x).\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "The total interest equation is\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "    0.07*(5000-x) + 0.09x = 390   dollars.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "From the equation\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "    x =  = 2000.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "ANSWER.  Investments are $2000 at 9% and the rest,  5000-2000 = 3000 dollars at 7%.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "CHECK.   0.09*2000 + 0.07*3000 = 390  dollars.   ! Precisely correct !\r\n" );
document.write( "

\r
\n" ); document.write( "\n" ); document.write( "Solved.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "----------------\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Every day we solve 3 - 5 similar problems at this forum.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "It is a standard and typical problem on investments.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "If you need more details, or if you want to see other similar problems solved by different methods, look into the lesson \r
\n" ); document.write( "\n" ); document.write( " - Using systems of equations to solve problems on investment\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "You will find there different approaches (using one equation or a system of two equations in two unknowns), as well as
\n" ); document.write( "different methods of solution to the equations (Substitution, Elimination).\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( " - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "The referred lesson is the part of this online textbook under the topic \"Systems of two linear equations in two unknowns\".\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

\n" );